A number of implantable bioprosthetic devices are currently being used for treating patients with cardiovascular diseases and defects. Such implantable devices are useful for replacing diseased, damaged, or congenitally malformed components of a patient's cardiovascular system. Thus, damaged or diseased heart valves have been replaced with chemically-fixed, bioprosthetic heart valves prepared from tissues of porcine or bovine origin. Similarly, regions of damaged or diseased blood vessels may also be replaced with bioprosthetic vessels prepared from bovine tissues.
Typically, the animal tissues used to form implantable devices are chemically cross-linked with agents, especially those animal tissue components that come into direct contact with the blood of a patient, and then chemically sterilized and preserved in a chemical solution. Such treatment is necessary to prevent rejection of the implanted bioprosthetic device by the recipient. Such treatment also stabilizes the protein components of the animal tissue, thus making them more resistant to degradation by proteolytic enzymes.
The use of chemically-treated implantable bioprosthetic devices presents several drawbacks, however. For example, the presence of chemically cross-linked/preserved agents, such as glutaraldehyde, presents an environmental hazard to the operating room personnel who are exposed to these chemicals as well as personnel involved in transporting such tissues. Consequently, preparation of chemically-treated devices in the operating room is a cumbersome and time consuming process as the chemical agents must be rinsed thoroughly off of the devices and then carefully crimped and loaded into a delivery catheter.